Interrupter apparatus



Oct. 2, 1956 A. BUCHMANN 2,765,377

INTERRUPTER APPARATUS I Filed- June 8, 1955 INVENTOR. Llaivcih);

Y ll B United rates Patent INTERRUPTER APPARATUS Alhin Bnchmann, Soleure, Switzerland, assignor to Scintilla Ltd., Soleure, Switzerland Application June 8, 1-953, SerialNo. 360,024

Claims'priority, application Switzerland June 6, 1952 -13Claims. (Cl. 200--30) The present invention relates to ignition systems for internal combustion engines, and more particularly to interrupter apparatus for such ignition systems.

With known interrupter apparatus it is inevitable that after a relatively short period of time the contacts of the'interrupter Will deteriorate, as by material of one of theconta'cts being transferred to the other of the contacts so that pits and projections form on'the'contacts which detract from the efliciency of the operation thereof and which soon necessitate replacement of the contacts; Although rriariy attempts have been made to solve this problem, as' for example, for providing one contact with a convex surface" mating with a flat surfaced contact, or providing contacts having a central bore, or even rotatory contacts, so far none of the known attempts to solve this problemhave proved to be satisfactory.

One of the objects of the present invention is to overcome the above drawbacks by providing an interrupter with a pair of movable contacts rather than with only one movable contact as is customary.

Another object of the present invention is to provide a means for simultaneously moving a pair of interrupter contacts into and out of engagement with each other respectively along substantially perpendicular paths.

A further object of the present invention is to provide a means for synchronizing the movement of a pair of interrupter contacts in such a way that the contacts do not slide with respect to each other when they move into and out of engagement with each other.

An additional object of the present invention is to provide a means for positively pressing one of the movable contacts against the other of the movable contacts when these contacts are in engagement With each other.

A still further object of the present invention is to provide a means for adjusting the position of one of the contacts.

With the above objects in view, the present invention mainly consists of an interrupter apparatus for interrupting an electrical circuit, this interrupter apparatus including a pair of contacts respectively carried by a pair of levers and a support means turnably supporting the levers. A cam means is turnably mounted on the support means and for turning the levers in synchronism to and from a position where the contacts engage each other.

The novel features which are considered as characteristic for the invention are set forth in particular in the appended claims; The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings, in which:

Fig. 1 isa partly sectional top plan view of an apparatusconstructed in accordance with the present invention;

Fig. 2 is a fragmentary sectional view taken along line A-A of Fig. 1 and extending above the plane of Fig. 1; and

Fig. 3 is a fragmentary sectional view taken along line z. of Fig. 1 and also extending above the plane of 1g.

Referring now to the drawings, the apparatus of the invention includes a support means in the form of a plate 2 located in a housing 1 of a magneto or distributor for an internal combustion engine. A shaft 3 adapted to be rotated about its axis by a suitable drive is turnable with respect to the plate 2 and is normal to and extends above the latter, this shaft 3 having a cam 4 fixed thereto for rotation therewith. This cam 4 has projecting cam portions 4' equidistantly distributed about the cam axis and being spaced from each other by intermediate peripheral portions of the cam 4 which are located at a lesser radial distance from the cam axis than the cam portions 4. In the particular example illustrated, four cam portions are provided so that the illustrated apparatus may be used with a four cylinder engine.

A lever 5 is turnably supported by the pivot pin 6 adjacent one end of lever 5 for turning movement about an axis parallel to the cam axis, and the lever 5 carries a contact 7 at its end distant from pivot 6. A second lever 9 is turnably supported adjacent one of its ends for turningmovement' about a bearing pin 14 Whose axis is parallel to the cam axis and located on the opposite side of cam 4 from pivot 6. This lever 9 carries at its end distant from pin 14 a second contact 8 which engages the contact 7 to close an electrical circuit (not shown), connected electrically to these contacts, when the levers 5 and 9 are in their circuit-closing position shown in solid lines in Fig; 1. As is apparent from Fig. 1, the levers 5 and 9 approach each other from the pins 6 and 14, respectively, and are substantially perpendicular to each other. Springs 20 and 21 respectively engage the levers 5 and 9' to urge the latter to the circuit-closingv position shown in'Fig. 1' in solid lines.-

As is most clearly shown in Fig. 3, a pair of rings 13 are fixed to the cam 4 on opposite sides of the cam portions 4' thereof for rotation with the cam 4, and the centers of these rings are in the cam axis, as is evident from Fig. 1. As is also evident from Fig. l, the rings 13 each have an outer periphery whose radius is smaller than the radial distance of the cam portions 4' from the cam axisand greater than the radial distance of the intermediate peripheral portions between cam portions 4 so that these rings project beyond these intermediate peripheral portions located between the projecting cam portions 4'.

The lever 5 is provided With a projection 5' extending toward the earn 4 and located closely adjacent to one of the intermediate peripheral portions of cam 4 when the lever 5 is in its circuit-closing position shown in solid lines in Fig. 1, this projection 5' having a thickness which is smaller than the distance between rings 13 and extendin'g slightly into the space between these rings but remaining' out of contact with earn 4 when the lever 5 is in its circuit-closing position so that the spring 20 through lever 5 positively urges the contact 7 against the contact 8.

The lever '9 is provided with a projection 9' fixed to a tubular'portion of lever 9, as shown in Fig. 3, and this projection 9 has a pair of opposite extensions which respectively engage the rings 13 when lever 9 is in its circuit-closing position so that these rings 13 serve to accurat'ely position the lever 9 so as to thereby accurately position the contact S for engagement with contact 7.

As is-most clearly shown in Fig. 2, the bearing pin 14 is turna'bly mounted on a pin 10 fixed to the plate 2 and extending through a bore of the bearing pin 14 which is parallel to and spaced from the axis of the bearing pin 14 so that this bearing pin is eccentrically mounted. The top end of the bearing pin is provided with projections 15 and a nut 16 is threaded to pin 10 and clamps bearing pin 14 against rotation. Thus, by loosening the nut 16 and engaging projections 15 to turn bearing pin 14 about pin 10, it is possible to adjust the position of lever 9 and contact 8 therewith. 1

The above-described apparatus operates as follows:

In the circuit-closing position of levers and 9 shown in solid lines in Fig. l, the contacts 7 and 8 have a common axis 11 and the projection 9 engages the rings 13 while the projection 5 extends freely between these rings and does not contact the cam 4 so that the spring 20 engaging lever 5 positively urges contact 7 against contact 8. Rotation of cam 4, upon rotation of shaft 3, causes a pair of successive cam portions 4 to simultaneously engage projections 5 and 9' to simultaneously move the levers 5 and 9 to the dotted line position shown in Fig. 1. In this position of the parts, the axis of contact 7 becomes located at 11 and the axis of contact 8 becomes located at 11', and it is evident that the contacts 7 and 8 respectively move along paths which are substantially perpendicular to each other. The continued rotation of cam 4 allows the levers 5 and 9 to move under the influence of springs 20 and 21 back to the solid line position shown in Fig. 1 where contacts 7 and 8 again have a common axis 11 and engage each other. The shape and arrangement of the parts is such that the contacts 7 and 8 move into and out of engagement with each other without any mutual sliding therebetween, and in this way wear of the contacts is avoided. By moving the axes of contacts 7 and 8 out of coincidence when these contacts are moved away from each other, the transfer of material from one contact to another is avoided.

It will be understood that each of the elements de scribed above, or two or more together, may also find a useful application in other types of interrupter apparatus differing from the types described above.

While the invention has been illustrated and described as embodied in interrupter apparatus having a pair of movable contacts, it is not intended to be limited to the details shown, since various modifications and structural changes may be made without departing in any way from the spirit of the present invention.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can by applying current knowledge readily adapt it for various applications without omitting features that, from the standpoint of prior art, fairly constitute essential characteristics of the generic or specific aspects of this invention and therefore, such adaptations should and are intended to be comprehended within the meaning and range of equivalence of the following claims.

What is claimed as new and desired to be secured by Letters Patent is: a

1. interrupter apparatus for interrupting an electrical circuit, comprising, in combination, a pair of contacts; a pair of levers respectively carrying said contacts; support means turnably supporting said levers; and cam means turnably mounted on said support means and for turning said levers in synchronism to and from a position where said contacts engage each other and for simultaneously moving said contacts respectively along a first and a second path, said first path being substantially perpendicular in its entirety to said second path.

2. interrupter apparatus for interrupting an electrical circuit, comprising, in combination, a pair of contacts; a pair of levers respectively carrying said contacts; support means turnably supporting said levers; cam means turnably mounted on said support means and for turning said levers in synchronism to and from a circuit-closing position where said contacts engage each other; and ring means carried by said cam means, being located about the turning axis thereof, and being engaged by a part of only one of said levers for accurately locating the contact carried by said one lever with respect to the other of said contacts when said contacts are in circuitclosing position.

3. Interrupter apparatus for interrupting an electrical circuit, comprising, in combination, a pair of contacts; a pair of levers respectively carrying said contacts; support means turnably supporting said levers; cam means turnably mounted on said support means for turning said levers in synchronism to and from a circuit-closing position where said contacts engage each other; ring means carried by said cam means, being located about the turning axis thereof, and being engaged by a part of only one of said levers for accurately locating the contact carried by said one lever with respect to the other of said contacts when said contacts are in circuit-closing position; and a bearing member eccentrically mounted on said support means and guiding said one lever for turning movement, said bearing member being turnable on said support means to adjust said one lever and the contact carried thereby.

4. Interrupter apparatus for interrupting an electrical circuit, comprising, in combination, a support; a first lever turnably mounted adjacent one end thereof on said support; a first contact mounted on said first lever adjacent an opposite end thereof; a second lever turnably mounted adjacent one end thereof on said support, having an opposite end adjacent said opposite end of said first lever and being substantially perpendicular to said first lever; a second contact mounted on said opposite end of said second lever and engaging said first contact when said levers are in a circuit-closing position; and cam means turnably mounted on said support between said levers for simultaneously turning said levers away from said circuit-closing position thereof so that said contacts simultaneously move along respective first and second paths, said first path being substantially perpendicular in its entirety to said second path.

5. interrupter apparatus for interrupting an electrical circuit, comprising, in combination, a support; a first lever turnably mounted adjacent one end thereof on said support; a first contact mounted on said first lever adjacent an opposite end thereof; a second lever turnably mounted adjacent one end thereof on said support, having an opposite end adjacent said opposite end of said first lever and being substantially perpendicular to said first lever; a second contact mounted on said opposite end of said second lever and engaging said first contact when said levers are in a circuit-closing position; cam means turnably mounted on said support between said levers for simultaneously turning said levers away from said circuit-closing position thereof so that said contacts simultaneously move along respective first and second paths, said first path being substantially perpendicular in its entirety to said second path; and biasing means for resiliently urging said levers toward said cam means.

6. Interrupter apparatus for interrupting an electrical circuit, comprising, in combination, a support; a first lever turnably mounted adjacent one end thereof on said support; a first contact mounted on said first lever adjacent an opposite end thereof; a second lever turnably mounted adjacent one end thereof on said support, having an opposite end adjacent said opposite end of said first lever and being substantially perpendicular to said first lever; a second contact mounted on said opposite end of said second lever and engaging said first contact when said levers are in a circuit-closing position; cam means turnably mounted on said support between said levers for simultaneously turning said levers away from said circuit-closing position thereof so that said contacts move in directions which are substantially perpendicular to each other; spring means operatively connected to said levers for urging the latter toward said cam means; and rings having their centers located in the turning axis of said cam means, being fixed to said cam means for rotation therewith, and engaging only said second lever When said levers are in said circuit-closing position thereof, said first lever being" out of contact with said cam means when said levers are in said circuit-closing position thereof and said spring means maintaining said first contact in engagement with' said second contact when said levers are in said circuit-closing position.

7. Interrupter apparatus for interrupting an electrical circuit, comprising, in combination, a support; a first lever turnably mounted adjacent one end thereof on said support; a first contact mounted on said first lever adjacent an opposite end thereof; a second lever turnably mounted adjacent one end thereof on said support, having an opposite end adjacent said opposite end of said first lever and being substantially perpendicular to said first lever; a second contact m-ountedon said opposite end of said second lever and engaging said first contact when said levers are in a circuit-closing position; cam means turnably mounted on said support between said levers for simultaneously turning said levers away from said circuit-closing position thereof so that said contacts move in'directions which are substantially perpendicular to each other; spring means operatively connected to said levers for urging the latter toward said cam means; rings having their centers located in the turning axis of said cam means, being fixed to said cam means for rotation therewith, and engaging only said second lever when said levers are in said circuit-closing position thereof, said first lever being out of contact with said cam mean when said levers are in said circuit-closing position thereof and said spring means maintaining said first contact in engagement with said second contact when said levers are in said circuit-closing position; and a bearing turnably mounted on said support and engaging said second lever to guide the latter for turning movement, said bearing being turnable about an axis parallel to and spaced from its own axis to adjust the position of said second lever.

8. interrupter apparatus for interrupting an electrical circuit comprising, in combination, a plate; a cam having its axis normal to said plate and being mounted on a shaft passing through said plate for rotation about said axis, said cam having a plurality of cam portions equidistantly distributed about said axis and a plurality of intermediate peripheral portions respectively located between said cam portions and being located nearer to the said axis than said cam portions; a pair of levers turnably mounted on said plate for respective rotation about axes parallel to said cam axis and located on opposite sides of said cam, said levers approaching each other and each having a projection extending toward said cam, said projections being respectively located closely adjacent to a pair of said intermediate peripheral portions of said cam when said levers are in a circuit-closing position so that the turning cam will simultaneously engage said projections with two cam portions, respectively, to simultaneously turn said levers away from said circuit-closing position thereof; a pair of contacts respectively mounted on said levers and engaging each other when said levers are in said circuit-closing position thereof said contacts simultaneously moving respectively along a first and a second path, said first path being substantially perpendicular in its entirety to said second path; and spring means operatively connected to said levers for urging the latter to said circuit-closing position thereof.

9. Interrupter apparatus for interrupting an electrical circuit comprising, in combination, a plate; a cam having its axis normal to said plate and being mounted on a shaft passing through said plate for rotation about said axis, said cam having a plurality of cam portions equidistantly distributed about said axis and a plurality of intermediate peripheral portions respectively located between said cam portions and being located nearer to the said axis than said cam portions; a pair of levers turnably mounted on said plate for respective rotation about axes parallel to said cam axis and located on opposite sides of said cam, said levers approaching each other and each having a projection extending toward said cam, said projections being respectively located closely adjacent to a pair of saidintermediate peripheral portions of said cam when said levers are in a circuitclosing position so that the turning cam will simultaneously engage said projections with two cam portions, respectively, to simultaneously turn said levers away from said circuit-closing position thereof; a pair of contacts respectively mounted on said levers and engaging each other when said levers are in said circuit-closing position thereof said contact simultaneously moving respectively along a first and a second path, said first path being substantially perpendicular in its entirety to said second path; spring means operatively connected to said levers for urging the latter to said circuit-closing position thereof; and rings having their centers located in said cam axis and being fixed to saidcam for rotation therewith, said rings having an outer periphery of a radius greater than the radial distance of said intermediate'peripheral por tions of said cam from said cam axis and smaller than the radial distance of said cam portions from said cam axis, and said ring engaging only one of said lever projections when said levers are in said circuit-closing posi-- tion thereof.

10. interrupter apparatus for interrupting an electrical circuit comprising, in combination, a plate; a cam having its axis normal to said plate and being mounted on a shaft passing through said plate for rotation about said axis, said cam having a plurality of cam portions equidistantly distributed about said axis and a plurality of intermediate peripheral portions respectively located between said cam portions and being located nearer to the said axis than said cam portions; a pair of levers turnably mounted on said plate for respective rotation about axes parallel to said cam axis and located on opposite sides of said earn, said levers approaching each other and each having a projection extending toward said cam, said projections being respectively located closely adjacent to a pair of said intermediate peripheral portions of said cam when said levers are in a circuit-closing position so that the turning cam will simultaneously engage said projections with two cam portions, respectively, to simultaneously turn said levers away from said circuit-closing position thereof; a pair of contacts respectively mounted on said levers and engaging each other when said levers are in said circuit-closing position thereof said contacts simultaneously moving respectively along a first and a second path, said first path being substantially perpendicular in its entirety to said second path; spring means operatively connected to said levers for urging the latter to said circuit-closing position thereof; rings having their centers located in said cam axis and being fixed to said cam for rotation therewith, said rings having an outer periphery of a radius greater than the radial distance of said intermediate peripheral portions of said earn from said cam axis and smaller than the radial distance of said cam portions from said cam axis, and said rings engagin only one of said lever projections when said levers are in said circuitclosing position thereof; and an elongated bearing pin engaging that one of said levers having said one projection to guide said one lever for turning movement, said bearing being mounted on said plate for turning movement about an axis parallel to and spaced from its own axis and parallel to said cam axis so that the position of said one lever may be adjusted by turning said bearing pin.

11. interrupter apparatus for interrupting an electrical circuit comprising, in combination, a plate; a cam having its axis normal to said plate and being mounted on a shaft passing through said plate for rotation about said axis, said cam having a plurality of carn portions equidistantly distributed about said axis and a plurality of intermediate peripheral portions respectively located between said cam portions and being located nearer to the said axis than said cam portions; a pair of levers turnably mounted on said plate for respective rotation about axes parallel to said cam axis and located on opposite sides of said cam,

said levers approaching each other and each having a projection extending toward said cam, said projections being respectively located closely adjacent to a pair of said intermediate peripheral portions of said cam when said levers are in a circuit-closing position so that the turning cam will simultaneously engage said projections with two cam portions, respectively, to simultaneously turn said levers away from said circuit-closing position thereof; a pair of contacts respectively mounted on said levers and engaging each other when said levers are in said circuit-closing position thereof said contacts simultaneously moving respectively along a first and a second path, said first path being substantially perpendicular in its entirety to said second path; spring means operatively connected to said levers for urging the latter to said circuit-closing position thereof; and a pair of rings respectively having their centers located in said cam axis and being fixed to said cam respectively on opposite sides of said cam portions thereof for rotation with said cam, said rings each having an outer periphery of a radius greater than the radial distance of said intermediate peripheral portions of said cam from said cam axis and smaller than the radial distance of said cam portions from said cam axis, and said rings engaging only one of said 8 lever projection when said levers are in said circuitclosing position thereof.

12. Apparatus as defined in claim 11 and wherein said one lever projection is provided with a pair of opposite extensions engaging said rings when said levers are in said circuit-closing position thereof.

13. Apparatus as defined in claim 12 and wherein the other of said lever projections has a free end of a lesser thickness than the distance between said rings located between said rings when said levers are in said circuitclosing position thereof.

References Cited in the file of this patent UNITED STATES PATENTS 1,168,638 Hoyt Ian. 18, 1916 1,413,905 Dean Apr. 25, 1922 1,436,693 Borger Nov. 28, 1922 1,981,996 Fjellstedt et al. Nov. 27, 1934 2,055,880 Pilla Sept. 29, 1936 2,070,072 Varela Feb. 9, 1937 2,425,190 Johnson et al. Aug. 5, 1947 2,624,810 Dietsche Jan. 6, 1953 

